This site will explain how to use "AppLocale"
software from Microsoft.

(1) What does "AppLocale" software do?

I have Windows XP English
version (USA). I am Japanese. I use both English and Japanese software. I can
set "Language for non-Unicode programs" option to Japanese. But when I did that,
my English business software became so slow. I use this business software every
day. I had no choice but set "Language..." option to English. Then again, I
can't use Japanese software.